Micro-incision IOL and positioning of the IOL in the eye

ABSTRACT

An intraocular lens that is capable of being inserted through a micro-incision includes an optic having an anterior and a posterior surface and a plurality of projections extending from the anterior and posterior surfaces. The anterior and posterior surfaces include a recess. The optic is implanted such that a rim of the capsulorhexis is disposed in the recess such that the plurality of projections grip the capsular bag.

CROSS-REFERENCES TO RELATED APPLICATIONS

This application is a continuation of and claims priority to U.S. patentapplication Ser. No. 14/196,658, filed Mar. 4, 2014, which claimspriority to U.S. Provisional Application No. 61/779,505 filed on Mar.13, 2013, the entire contents of which are incorporated herein byreference.

BACKGROUND

Field of the Invention

This invention relates generally to intraocular lenses, and morespecifically, to compact intraocular lenses that can be implanted in theeye with a micro-incision.

Description of the Related Art

A human eye can suffer diseases that impair a patient's vision. Forexample, a cataract can increase the opacity of the lens, ultimatelyleading to blindness. To restore the patient's vision, the diseased lensmay be surgically removed and replaced with an artificial lens, known asan intraocular lens, or IOL. As another example, to treat eye conditionssuch as myopia, hypermetropia or presbyopia, an intraocular lens can besurgically implanted in the eye to replace or supplement the naturaleye.

IOLs can be inserted in the eye through an incision in the eye. Theincision size can depend on the material of the IOL, size and structureof the IOL and the mode in which the IOL is delivered in the eye. Forexample, the incision size can be about 10-12 mm in standardextracapsular surgery, about 5.5-7.0 mm in manual small incision surgeryand about 3.0-5.5 mm if phacoemulsification methods are used. Reducingthe size of the incision can reduce the complexity of the surgicalprocedure, reduce post-surgical recovery time and reduce patientdiscomfort. IOLs that can be implanted in the eye throughmicro-incisions can advantageously increase patient safety, reducerecovery time and patient discomfort.

SUMMARY

IOLs can be implanted in the eye to correct for a variety of visiondefects. IOLs can be introduced in the eye through an incision made inthe corneal layers and implanted in the capsular bag or in front of thecapsular bag. Conventional IOL designs and insertion procedures enableIOLs to be inserted through incisions that range in size between 3.0mm-12 mm. While conventional IOLs and methods of implantation providethe end result of treating the vision conditions in question, it isadvantageous to reduce the size of the incision made to access theinside of the eye. Smaller incisions will reduce the complexity of thesurgical procedure, reduce post-surgical recovery time and reducepatient discomfort. Certain embodiments disclosed herein include compactIOLs that are capable of being inserted through micro-incisions, suchas, for example incisions that are a few hundred microns in size.

Embodiments of the IOLs disclosed herein comprise an optic adapted tofocus light on the retina when disposed in the eye and a haptic ormounting structure that is operably coupled to the optic. In one aspectthe haptics can be small and soft such that the IOL can be folded orrolled so as to occupy a smaller volume as compared to current IOLdesigns.

In another aspect, the optic of the IOL embodiments disclosed herein canbe configured to be in tension when deployed in the eye, e.g., subjectto stretching forces applied transverse to the optical axis of the IOL,which can maintain a thin deployed configuration that retains itsstructural integrity.

In another aspect, an intraocular lens comprises an optic disposed aboutan optical axis, the optic having an anterior surface and a posteriorsurface with at least one anterior projection coupled to and extendingradially from the optic and at least one posterior projection adjacentto the at least one anterior projection, wherein the at least oneposterior projection is coupled to and extends radially from the optic.The anterior and posterior projections are resiliently biased such thatdistal ends of the anterior projection and the posterior projection canbe moved away from and toward each other. When implanted, the distalends of at least one of the anterior projection and the posteriorprojection is configured to grip at least one of an outside surface andan inside surface adjacent to a capsulorhexis on an anterior portion ofan evacuated capsular bag. At least one of the surfaces may include adiffractive surface. In addition, the anterior and posterior projectionmay be actuated by axially compressing a zone disposed between the opticand distal ends of the anterior and/or posterior projection. Whenimplanted in the eye, the optic may be subject to stretching forceapplied transverse to the optical axis. The stretching force may bedistributed uniformly across the surface of the optic. In addition,there may be a recess between the anterior and posterior projections.The recess may have protrusions for securing the IOL to the capsularbag, and the protrusions may be shaped as barbs or teeth. Whenimplanted, the rim of the capsulorhexis may be disposed in the recess.When implanted in the eye, the optic is partially in the capsular bagand partially outside the capsular bag.

Details of one or more implementations of the subject matter describedin this specification are set forth in the accompanying drawings and thedescription below. Other features, aspects, and advantages will becomeapparent from the description, the drawings, and the claims. Thedrawings depicting novel and non-obvious aspects of the invention arefor illustrative purposes only. Note that the relative dimensions of thefollowing figures may not be drawn to scale.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings include the following figures in which like numerals referto like parts.

FIG. 1 is a diagram illustrating the relevant structures of the humaneye.

FIG. 2A is a perspective view of an implementation of an IOL that can bemounted on the anterior portion of the capsular bag. FIG. 2B is across-sectional view of the IOL illustrated in FIG. 2A as mounted on aportion of the anterior portion of the capsular bag.

FIG. 2C is a perspective view of another implementation of an IOL thatcan be mounted on the anterior portion of the capsular bag.

FIG. 3A illustrates a side view of a diffractive optic included in theIOL illustrated in FIG. 2A. FIG. 3B illustrates the front view of thediffractive optic illustrated in FIG. 3A.

FIG. 4 illustrates a cross-sectional view of the IOL illustrated in FIG.2B mounted on the capsular bag in conjunction with a dual optic IOLmounted in the capsular bag.

FIGS. 5A and 5B are cross-sectional views showing the exemplary recessesfor the IOL illustrated in FIG. 2A.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

It is to be understood that the figures and descriptions of the presentinvention have been simplified to illustrate elements that are relevantfor a clear understanding of the present invention, while eliminating,for the purpose of clarity, many other elements found in typical lenses,lens systems and lens design methods. Those of ordinary skill in thearts may recognize that other elements and/or steps are desirable andmay be used in implementing the embodiments described herein.

FIG. 1 is a schematic drawing of a human eye 100. Light enters the eyefrom the left of FIG. 1, and passes through the cornea 110, the anteriorchamber 120, a pupil defined by the iris 130, and enters the lens 140.After passing through the lens 140, light passes through the vitreouschamber 150, and strikes the retina 160, which detects the light andconverts it to a signal transmitted through the optic nerve to the brain(not shown).

The natural lens 140 is a transparent crystalline biconvex optic that ishoused in a structure known as the capsular bag 145. The lens 140 canfocus light from objects over a wide range of distances on the retina bychanging its shape thereby changing its focal length. The ability of thelens 140 to change its shape to adjust the focal length is known asaccommodation. During accommodation, the natural lens 140 is acted on byocular forces generated by ciliary muscles, zonular fibers (also knownas zonules) and the capsular bag. For example, the ciliary muscles andthe zonular fibers can pull on the capsular bag to change its shape. Themotion of the capsular bag generally deforms the natural lens 140 inorder to change its refractive power and/or the location of the lens140, so that the eye can focus on objects at varying distances away fromthe eye.

To treat patients suffering from various eye diseases such as myopia,hypermetropia, presbyopia, cataract, etc., an intraocular lens (IOL) isinserted into the eye to replace or augment the natural lens 140. TheIOLs can be configured such that they can be rolled and/or compactedprior to insertion and inserted into the eye through incisions thatrange in size between 3.0 mm-12.0 mm. The IOLs can be configured tounroll and/or expand after insertion into the eye. The IOL can beintroduced in the eye through an incision made in the corneal layers andimplanted either in the capsular bag 145 or in front of the capsular bag145 or partly in the capsular bag 145 and partly outside the capsularbag 145. To implant the IOL either partially or completely in thecapsular bag 145, the diseased natural lens 140 can be removed from theeye by a process known as phacoemulsification. Duringphacoemulsification, an opening is created in the anterior portion ofthe capsular bag 145 by a process known as capsulorhexis and thediseased lens is removed. In various implementations, a pulsed laser(e.g. a femtosecond laser) can be used to create an opening in theanterior portion of the capsular bag 145 by ablating a pattern onto thedesired area of the capsular bag 145. The capsulorhexis produced bypulsed lasers can be highly reproducible. The energy, frequency and theduty cycle of the pulsed lasers can be varied to produce a capsulorhexis that is precisely sized and shaped to suit the needs of thepatient. The use of pulsed laser in capsulorhexis can reduce theincidence of tears in the capsular bag 145 which can aid in maintainingthe strength and the integrity of the capsular bag 145. Pulsed laserscan be also used to create openings that are regularly shaped andwell-centered. A well-centered and regularly shaped capsulorhexis canreduce the possibility of the IOL being decentered or tilted which canadversely affect the quality of vision. Additionally, the edge of thecapsulorhexis produced by pulsed lasers can be smooth such that thevision through the IOL is not impacted.

IOLs designed for placement in the capsular bag are generally of avolume requiring an incision of significant size. For example, the IOLcan be bulky such that it is properly anchored in the capsular bag anddoes not get decentered or tilted during operation. As another example,some accommodating IOL designs are intended to substantially fill thecapsular bag in operation. While there are good reasons for suchdesigns, such as to more closely mimic the natural eye function and toavoid a shrink-wrapping effect of the evacuated capsular bag, the netresult is either a larger incision size or a much more complex injectorsystem to minimize incision size growth. These and other issues canresult in a patient being subject to incisions in the range of 3.0-12.0mm for the placement of an IOL. As discussed above, it is advantageousto design IOLs that can be inserted through an incision smaller than 3.0mm, for example, incisions in the range of about 100 μm to about 1 mm.

The embodiments of IOLs disclosed herein are configured to be implantedpartially in the capsular bag 145 and partially outside the capsular bag145. In particular the embodiments of the IOLs disclosed herein areconfigured to be disposed on the rim of the capsulorhexis. Theembodiments of the IOLs disclosed herein include soft and compacthaptics that allow the IOLs to be inserted in the eye throughmicro-incisions. Furthermore, the soft and compact haptics areconfigured to grip, clip, clasp or clamp onto the rim of thecapsulorhexis. Various implementations of the IOLs described herein alsoinclude thin and compact optics that can retain their structuralintegrity when maintained under tension. The optic of the IOLembodiments disclosed herein can be configured to be in tension whendeployed in the eye, e.g., subject to stretching forces appliedtransverse to the optical axis of the IOL.

FIG. 2A is a perspective view of an implementation of an IOL that can bemounted on the anterior portion of the capsular bag, for example, on therim of the capsulorhexis. FIG. 2B is a cross-sectional view of the IOLillustrated in FIG. 2A as mounted on the anterior portion of thecapsular bag. The IOL 200 includes an optic 205 intersected by anoptical axis B-B′. The optic 205 can include an optically transmissiveand a deformable material, such as, for example, acrylic, silicone,PMMA, PDMS, hydro-siloxane, etc. In various implementations, the optic205 may be implanted in the eye such that the optic is maintained undertension or is stretched and has a thickness between about 100 μm and 1.5mm along the optical axis B-B′. In various implementations, the optic205 can have a biconvex shape, a meniscus shape, a plano-convex shape, aplano shape, etc. The optic 205 has an anterior surface 207 a facing theiris 130 of the eye and a posterior surface 207 b opposite the anteriorsurface 207 a. The anterior surface 207 a and/or or the posteriorsurface 207 b can be curved such that the optic 205 has a refractivepower. In various implementations, the anterior surface 207 a and/or theposterior surface 207 b can include diffractive features such that theoptic 205 has a diffractive power. Particular implementations ofdiffractive optics are discussed below with reference to FIGS. 3A and 3Bbelow. In various implementations, the optic 205 can be monofocal,bifocal or multifocal. In some implementations, the optic 205 caninclude antireflective coatings and/or coatings that reduce glare. Invarious implementations, the IOL 200 can include a plurality of optics.For example, in some embodiments, the IOL 200 can be a dual optic.

The IOL 200 includes a plurality of projections 210 a, 210 b, 212 a, 212b, 215 a, 215 b, 217 a and 217 b that are disposed along the peripheryof the optic 205 and extend outward from the optic, preferably from theanterior surface 207 a and the posterior surface 207 b of the optic 205.The plurality of projections can be arranged in pairs (e.g. 210 a and210 b, 212 a and 212 b, 215 a and 215 b, 217 a and 217 b) such thatevery projection that extends from the anterior surface 207 a has acorresponding projection that extends from the posterior surface 207 b.Each pair of projections includes a groove or a recess 211 between them.In various implementations the groove or recess 211 can include a curvedsurface. The groove or recess 211 is configured to receive a part of theanterior portion of the capsular bag 145 such that each pair ofprojections (210 a and 210 b, 212 a and 212 b, 215 a and 215 b, 217 aand 217 b) clasp, grasp, grip or clip onto the rim of the capsulorhexis.For example, as shown in FIG. 2B, a first part of the anterior portionof the capsular bag 145 that forms the rim of the capsulorhexis isdisposed in the recess 211. The first part of the anterior portion ofthe capsular bag is pinched or sandwiched between the two projections210 a and 210 b when the capsular bag is so positioned. Similarly, theprojections 215 a and 215 b of the haptic structure 215 pinch orsandwich a second part of the anterior portion of the capsular bag 145that forms the rim of the capsulorhexis. When a part of the capsular bag145 is inserted into the groove or recess 211 the anterior projection210 a grips on to the front surface of the anterior portion of thecapsular bag 145 and the posterior projection 210 b grips on to the rearsurface of the anterior portion of the capsular bag 145.

In some implementations, each projection can be an individual structurethat is attached to the anterior surface 207 a or the posterior surface207 b of the optic 205. For example, with reference to FIG. 2A,projections 210 a, 212 a, 215 a and 217 a extend from the anteriorsurface 207 a of the optic 205 and the projections 210 b, 212 b, 215 band 217 b extend from the posterior surface 207 b of the optic 205. Insome implementations, the pair of projections can be a part of abifurcated haptic structure. For example, with reference to FIG. 2B, thepair of projections 210 a and 210 b can be a part of a bifurcated hapticstructure 210 that extends from the periphery of the optic 205.

In the implementation illustrated in FIG. 2A, the plurality ofprojections 210 a, 212 a, 215 a and 217 a (or the plurality ofprojections 210 b, 212 b, 215 b and 217 b) are arranged around theanterior surface 207 a (or the posterior surface 207 b) of the optic 205such that adjacent projections are disposed approximately at rightangles with each other. Stated another way, when viewed from the front,an angle of about 90 degrees is defined between lines extending out froma central optical axis of the surface 207 a to the circumferentialmid-point of nearest neighboring projections. However, in otherembodiments, the plurality of projections 210 a, 212 a, 215 a and 217 a(or the plurality of projections 210 b, 212 b, 215 b and 217 b) can bearranged such that adjacent haptic structures are disposed at anglesless than or greater than 90 degrees with each other. Although, in theembodiment shown in FIG. 2A four projections extend from the anteriorsurface 207 a and the posterior surface 207 b, in other embodiments one,two, three, five, six, eight, twelve or more projections can extend fromeach surface of the optic. In various implementations, the plurality ofanterior projections may be united to form a continuous anterior ring230 that is disposed around the anterior surface 207 a of the optic 205as illustrated in FIG. 2C. Similarly the plurality of posteriorprojections may be united to form a continuous posterior ring 240 thatis disposed around the posterior surface 207 b of the optic 205 asillustrated in FIG. 2C. The anterior and posterior rings can include acontinuous groove or recess 221 as shown in FIG. 2C.

As noted above, the IOL 200 is intended to be insertable through amicro-incision. As such, the material of the optic 205, the material ofthe plurality of projections, the dimensions of the optic 205 and thesize of the plurality of projections are preferably selected such thatthe IOL 200 can be rolled, folded and/or compacted to have a smallvolume, for example, between about 10 mm³ and 40 mm³ to allow insertionthrough a micro-incision. To facilitate insertion of the IOL, theplurality of projections is preferably configured to occupy a lowprofile for delivery through such an incision. For example, plurality ofprojections can be small and have a linear dimension that is in therange of about 0.2 mm and about 1.5 mm.

The IOL 200 can be attached to the evacuated capsular bag 145 afterphacoemulsification. In one method of attachment, the IOL 200 is placedover the opening created in the capsular bag 145 duringphacoemulsification such that the portion of the capsular bag 145 thatforms the rim of the capsulorhexis is inserted into the groove 211 suchthat the anterior projections 210 a, 212 a, 215 a and 217 a are adjacentthe front surface of the anterior portion of the capsular bag 145 andthe posterior projections 210 b, 212 b, 215 b and 217 b are adjacent therear surface of the anterior portion of the capsular bag 145. The IOL200 is mechanically attached to the rim of the anterior surface of thecapsular bag 145 by bringing the plurality of projections toward thefront and rear surface of the anterior portion of the capsular bag 145such that the plurality of projections grips the anterior portion of thecapsular bag 145. In various implementations, the IOL 200 can be placedover the opening created in the capsular bag 145 such that a part of theIOL 200 is inside the evacuated capsular bag 145 and a part of the IOL200 is outside the evacuated capsular bag 145.

In various implementations, the plurality of projections 210 a, 210 b,212 a, 212 b, 215 a, 215 b, 217 a and 217 b can include a softbio-compatible elastic material to facilitate the attachment of theoptic 205 to the rim of the capsulorhexis. Various implementations ofthe IOL 200 can be formed such that in the resting or natural state, thepair of projections 210 a and 210 b, 212 a and 212 b, 215 a and 215 b,217 and 217 b can be configured to be in contact with each other. Insuch implementations, each pair of projections 210 a and 210 b can beheld in contact with each other by a spring force resulting from theshape and the material of the projections. In some such implementations,each pair of projections 210 a and 210 b can be held in contact witheach other by adhesive forces (e.g. hydrophilic attractive force,chemical stiction forces, etc.). When such implementations are implantedin the eye, a parting force (e.g. force applied by forceps) can beapplied to space apart each pair of projections from each other and apart of the capsular bag 145 is inserted into the groove or recess 211.Subsequently, when the parting force is removed, the projections claspon to the part of the inserted capsular bag 145 due to the tendency ofthe projections to return to their initial resting state.

Some implementations of the IOL 200 can be formed such that in theresting or natural state, each pair of projections are spaced apart fromeach other. In such implementations, when the IOL 200 is implanted inthe eye a part of the capsular bag 145 is inserted in the recess 211.Subsequently a pinching force (e.g. force applied by forceps) is appliedto bring each pair of projections toward each other such that the partof the inserted capsular bag is securely pinched or sandwiched betweeneach pair of projections. In various implementations, the pair ofprojections can be laser welded together after implantation to moresecurely attach the optic.

As seen in FIGS. 5A and 5B, the recess 211 can have detailed geometries,in order to maximize the clamping and stretching geometry, as well asease IOL implantation. The preferred embodiments maximize the grip ontothe capsular bag 145, through teeth-like protrusions 510 and 511, whichfunction as gentle barbs to hold the IOL to the capsular bag.

In various implementations, the optic 205 can be maintained undertension when implanted in the eye. For example, in one method ofimplantation, the optic 205 can be attached to a first part of the rimof the capsulorhexis, as described above. Subsequently, the IOL 200 canbe stretched to attach to a second part of the rim of the capsulorhexis.The optic 205 is thus subject to stretching forces that are appliedtransverse to the optical axis B-B′. Since, the optics 205 can bemaintained under tension, the optic 205 can have a slim profile whilestill have structural integrity. In other words, the optic 205 can bemade thinner than optics for accommodating IOLs which have a certainminimum thickness in order to have structural stability duringaccommodation. Such optics can be advantageously inserted throughmicro-incisions. Another possible advantage of the variousimplementations of IOL 200 discussed above, is that they can berelatively insensitive to tilt or decentering as compared to otheraccommodating IOLs that are mounted in the capsular bag 145.

Based on the distribution of the plurality projections, the optic 205can be stretched symmetrically or asymmetrically in various radialdirections. For example, the optic 205 can be symmetrically stretched inall radial directions, if the projections are uniformly distributedalong the entire periphery of the optic 205 with sufficiently highdensity. However, if the projections are not uniformly distributed alongthe entire periphery of the optic 205 or if the density of theprojections is small (e.g. two projections, four projections, etc.) thenthe optic 205 can be asymmetrically stretched in different directions.Asymmetrical stretching can be advantageous to provide toric ormultifocal lenses where different portions of the optic 205 can bestretched differently to provide different add powers. The different addpowers can be at different diameters of the optic 205 to eliminate orinduce astigmatism or can be configured to provide multiple foci forviewing a combination of near, intermediate, and far.

As discussed above, the optic 205 can have a slim profile to allowinsertion through micro-incisions. In such implementations, it may notbe practical to provide high refractive power. Accordingly, optics withslim profiles can include diffractive features to provide additionaldiffractive power when the refractive power provided by such optics isnot sufficient to suit the patient's needs. FIGS. 3A and 3B illustrateimplementations of a diffractive lens 300 that can provide diffractivepower. The diffractive lens 300 includes an optic 205 with a slimprofile and a plurality of diffractive features 350. The diffractivefeatures 350 can be disposed on the anterior surface 207 a of the optic205 or the posterior surface 207 b of the optic 205 or both the anteriorand the posterior surfaces. The diffractive features 350 can include aplurality of surface relief features or volume features. In variousimplementations, the diffractive features 350 can be embossed, etched orprinted directly on the surface of the optic. In other implementations,a coating including the diffractive features 350 can be laminated ontothe surface of the optic 205.

The diffractive lens 300 can be configured as a thin optical elementthat can be maintained under tension while still maintaining structuralintegrity. The plurality of diffractive features 350 can be arranged asa plurality of concentric zones, with spacings between adjacent zonesprogressively decreasing at increasing distance away from the center ofthe diffractive lens 300. The amount of diffractive power provided bythe diffractive lens 300 is determined in part by the zone diameters.Within each zone, the surface profile has a particular profile height,which may or may not be constant throughout the zone. For instance, thesurface profile may increase in height from the inside to the outside ofthe zone.

A specific example of a slim diffractive profile is a multi orderdiffractive lens. Such lenses are described in U.S. Pat. No. 5,589,982.The combination of this thin diffractive lens and an attachment to thecapsular bag has specific advantages. Because of the capsularattachment, the optic may be subjected to stretching forces only. Thisis in contrast to the compressive forces, in optics being positioned inthe capsular bag using the traditional haptics (the haptics arecompressed in the capsular bag, and these compressive forces are guidedthrough the optic). As a result, in the current invention, the optic canbe made extremely thin, without losing structural stability.Consequently, the thin lens can have the shape of a thin film, beingstretched across the capsulorhexis opening.

In various implementations, the capsulorhexis mounted IOL 200 can beimplanted in the eye along with another IOL that is implanted in thecapsular bag 145 or in front of the capsular bag 145. By way of example,FIG. 4 illustrates a cross-sectional view of the capsulorhexis mountedIOL 200 illustrated in FIGS. 2A-3B mounted on the capsular bag alongwith a dual optic IOL located in the capsular bag 145. In suchimplementations the capsulorhexis mounted IOL 200 can augment the visualeffects provided by another IOL implanted in the eye. For example, invarious implementations, the capsulorhexis mounted IOL 200 can provideadditional add power that improves the vision of the patient. As anotherexample, in some implementations, the capsulorhexis mounted IOL 200 cancorrect for defects and aberrations that result after another IOL isimplanted in the eye.

Although the invention has been described and pictured in an exemplaryform with a certain degree of particularity, it should be understoodthat the present disclosure of the exemplary form has been made by wayof example, and that numerous changes in the details of construction andcombination and arrangement of parts and steps may be made withoutdeparting from the spirit and scope of the invention as set forth in theclaims hereinafter.

What is claimed is:
 1. An intraocular lens comprising: an optic disposedabout an optical axis, the optic having an anterior surface and aposterior surface; at least two anterior projections coupled to andextending radially from the optic; and at least two posteriorprojections adjacent to the at least two anterior projections, whereinthe at least two posterior projections are coupled to and extendsradially from the optic, wherein the anterior and posterior projectionsare resiliently biased such that distal ends of the anterior projectionsand the posterior projections can be moved away from and toward eachother, and wherein, when implanted, the distal ends of the at least twoanterior projections and the at least two posterior projections areconfigured to grip an outside surface and an inside surface adjacent toa capsulorhexis on an anterior portion of an evacuated capsular bag. 2.The intraocular lens of claim 1, wherein the anterior and posteriorprojections are actuated by axially compressing a zone disposed betweenthe optic and distal ends of the anterior and/or posterior projections.3. The intraocular lens of claim 1, wherein, when implanted in the eye,the optic is subject to a stretching force applied transverse to theoptical axis.
 4. The intraocular lens of claim 3, wherein the stretchingforce is distributed uniformly across the surface of the optic.
 5. Theintraocular lens of claim 1, further comprising a recess between theanterior and posterior projections.
 6. The intraocular lens of claim 5,wherein, when implanted, the rim of the capsulorhexis is disposed in therecess.
 7. The intraocular lens of claim 1, wherein, when implanted inthe eye, the optic is located partially in the capsular bag andpartially outside the capsular bag.